Monday, August 22, 2011

They are one of the world's most unique animals as well as the iconic symbol of Australia.

Scientists have finally got to the bottom of why the kangaroo acts and looks like it does, and more importantly have unveiled the secret of its hop.

By sequencing its DNA for the first time, a team of international academics has also got to understand how the species has evolved over 130million years.

Hop to it: Scientists have finally got to the bottom of why the kangaroo bounces along after sequencing its DNA for the first time

They achieved this by focusing on a very small species of kangaroo, the tammar wallaby - Macropus eugenii - that lives quietly on small islands off Australia's southern and western coastlines.

In addition to zeroing in on its hop genes, other exciting discoveries from the genome included the 1,500 smell detector genes responsible for the tammar wallaby's excellent sense of smell, and genes that make antibiotics in the mother's milk in order to protect kangaroo newborns from E. coli and other harmful bacteria.

It is only the third marsupial to have its genome sequenced after the Tasmanian devil and the South American opossum.

Experts say the first kangaroo genome is a huge moment for scientific discovery, telling them how ancestors of kangaroos and other marsupials evolved from other mammals.

'The tammar wallaby sequencing project has provided us with many possibilities for understanding how marsupials are so different to us,' said Marilyn Renfree from the University of Melbourne.

Professor Renfree was one of the lead researchers on the project, which was conducted by an international consortium of scientists from Australia, USA, Japan, England and Germany.

The kangaroo is only the third marsupial to have its genome sequenced after the Tasmanian devil and the South American opossum

Tammar wallabies have many intriguing biological characteristics.

For example, the 12 month gestation includes an 11 month period of suspended animation in the womb.

At birth, the young weigh only half a gram, and spend 9 months in the mother's pouch, where the newborn babies reside for protection.

Researchers hope that the genome sequence will offer clues as to how tammar wallaby genes regulate these fascinating features of kangaroo life.

Professor Renfree added lessons to be learned from the tammar wallaby genome 'may well be helpful in producing future treatments for human disease.'

They also plan to look at how the kangaroo's genome sequence is complemented by the 'transcriptome' sequence, which represents a catalogue of how strongly each gene is turned 'on' or 'off' at different stages of the tammar life cycle and in different parts of the body.

Study of the transcriptome will allow many more interesting questions to be asked about how kangaroo genes compare to their counterparts in humans.

The findings are published in the Biomed Central journal, Genome Biology.